Optimizing the use of a skin prick test device on children

Studies comparing skin prick test (SPT) devices have revealed varying results in performance and there is little known about their use on children.

We performed 2 complementary studies to test the sensitivity, reproducibility and acceptability of commercially available SPT devices (Stallerpoint, Antony, France) using different application techniques. In the first part, histamine/saline was put on as a drop by use of a vial (V), and in the second part it was transferred from a well with the aid of the test device (W). The techniques were as follows: apply vertical pressure (Stallerpoint-VP or Stallerpoint-WP), apply vertical pressure with 90° clockwise rotation (Stallerpoint-VC or Stallerpoint-WC) and apply vertical pressure with 90° clockwise and counter-clockwise rotations (Stallerpoint-VCC or Stallerpoint-WCC). For comparison, ALK Lancet was used with a technique of 'drop and apply vertical pressure'.

In the first part, sensitivities of the Stallerpoint-VC (96.6%), Stallerpoint-VCC (95.5%) and ALK Lancet (93.2%) techniques were superior (p < 0.001) to the other Stallerpoint-VP and Stallerpoint-WP techniques (76.1 and 46.6%). Intrapatient coefficient of variation (CV) values were 15.0, 18.9, 15.4, 22.4 and 48.5%, respectively. Interpatient CV ranged between 22.8 and 55.1%. In the second part, the Stallerpoint-WC (98.8%), WCC (97.5%) and ALK Lancet (98.8%) techniques yielded high sensitivities, whereas the sensitivity of Stallerpoint-WP (28.7%) was very low. There were false-positive reactions in the Stallerpoint-VCC and WCC techniques.

In children, the SPT technique was found to be as important as the testing device. Stallerpoint-VC and WC techniques are reliable, tolerable and comparable with the ALK Lancet technique.